And he who posted it asked about the opinions of using Holethrough caps.

And well again I was reminded of a horrible motherboard sent to me for a fix after a failed recap.

This was the board, YES! that two black things at keyboardconnector sure IS 22uF caps.

So let us go through some basic stuff:

WHY Recap?

ok, Amiga 600, 1200, 4000, CD32, CD32 FMV Module, A4000 030 and 040 CPU cards all suffer of leakage. When the caps leaks it eats up your motherboard and after a while destroys it. OFTEN it is noted by bad composite out, bad audio. also effects like nonboot (CD32, A600), or cracking noises or distorded audio.

And when you have issues like distorded audio, just a change of capacitors will not do it (recap) so it is better to have your machine recapped BEFORE you are having any issues.

How to notice leakageissues? Well first of all, not always those issues are visible. a board can look perfectly fine and when removing caps you notice leakage.

BUT often you can see some dull colors at the bottom of the caps, like this example:

at the arrows you can see that there is a grey/greeish color and not as shiny as it should be. the darker the worse.

So what you need to do is to replace them, and I would recomend to change them all while doing it.

so.. HOW do you remove it? at the link at the top, they say that you can twist them off.

ok. well you CAN take your magnum and SHOOT them off the board if you like to. But it is TOTALLY wrong.

WHY?

Simple, look at the board, the pads they are small. (like 2x3mm) and are glued to the PCB. they are not designed for the force applied when removing the caps with force. it CAN work but it can also fail so you need to do a lot of extra work, especially when dealing with weakend pads due to the leakage. so twisting, wiggeling, cutting them off stresses the PCB more then it was designed for, especially with old stuff like the Amiga. There are only 2 days that works good:

Hot Tweezers, this is like a tweezer of 2 solderingirons, heating up both spots at the same time, so you can easy remove them

Hotair station, there are really ok hotairstations now for more or less nothing on E-Bay like the Atten 858D, they are really nice, and with a temperature of aprox 280 degrees it is quite easy to remove the caps without damaging surrounding plastics.

So simply: Do NEVER apply force when removing SMD caps, NEVER EVER. there is no excuse even if it MIGHT work most of the times. but usually you DO rip a pad or so making the recap much harder.

OK. New caps then. what to use?

First of all: Commodore have calculated a lot when designing the machines, of types etc. BUT also: during production you want to cut costs. You simply does not put in the best stuff as it costs too much, and ACTUALLY . you want customers to buy more machines later, so they should not last too long.

Through-hole caps: again, in the link above he uses throughhole caps.
YET again, this is just WRONG!. even if they MIGHT leak less (they sure can leak aswell!), again they are not designed for SMD installation. SO the pads on the PCB is stressed from the caps. Vibration if you move it, expansion when the machine gets hot/cold. Remember it took aprox 20 years before there was issues with the LOW QUALITY caps commodore used, the stress from holethrough caps can also take several years before they get noticed.. at my picture above, I do not need to tell you that the pads for the audiocaps (22uF, the BIG black ones) was loose. but also pads for other locations replaced with holethrough caps.

There is NO reason whatsoever to put in holethrough caps except one thing: You cannot solder SMD! and that is false as it is actually HARDER to solder in trough hole caps on SMD locations then real SMD caps.

Ceramic Caps: Well People are putting in ceramics instead as “they will not leak”. This is very true YES, instead they short and makes very ugly HARD to repair burnmarks on the motherboard. AND also they have totally different
characteristics than electrolytes. So it will not work as Commodore designed it for.

Tantalum Caps: Ok this is somewhat better then Ceramics, but yet again, different
characteristics than electrolytes, they do not leak, true. intead they can explode making more damage on the motherboard, also handles ripple etc different.

One VERY simple rule here: keep within the same type then it will work as Commodore once planned to it. a booting machine is NO proof of working caps whatsoever. remember that the Amiga boots without any of the electrolytes installed (but no audio, composite out etc.. but will boot) so even with leaking BAD caps it can behave like it works.

I myself use Panasonics Hybridcaps. (a nonformatted list at the end of this post) that have proven to work just fine, they DO cost some. but this is the Amiga, it is worth it.

Contact a peson with good reputation of recapping using SMD electrolyte caps

Ship it to the person above

Wait

Recieve Package from person

Install motherboard into your case

Enjoy

SIMPLY!: if you need a guide: DO NOT DO IT!.

Interested to learn? dig up D-Link routers, remove components, replace them on and on and on again until you do not make misstakes.. THEN you can do your Amiga rework. NEVER EVER practise on the Amiga. it MIGHT look simple, but I have got so many board with problems as people practised on their beloved Amigas.

removing components from the Dlink etc might be harder as they use leadfree solder, but then you learn more.

So simply: NO force when removing caps, no throughhole, and keep the same type.

I have just recapped an A1200, using a kit bought over the web with the correct capacitors although I think the 10uF ones are smaller and 16v.

The process went fine, no broken traces and the A1200 boots fine. For some minutes I have normal screen and colors, but a few minutes later I notice the RED turned into a light magenta and the colors looks washed and with too much bright/contrast.

You claim that A4000 has two 22uF capacitors mounted wrong on motherboard. You people still spread this nonsense? Are you capable of measure the voltages with an oscilloscope to see that you are writing nonsense (yet again)?

yes. to measure it. put the negative probe on your oscilloscope on the negative part of the cap, and the positive on the positive part of the cap and watch the swing go between 0 and -2.4V aprox. Meaning they are turned the wrong way..

You don’t mention the older models – does this mean that 500s and 3000s (those are the ones I got) don’t need re-capping? I’ve read that at least the power supplies should get new capacitors. What’s your take on this?